Gay activists have criticised the Vatican after its secretary of state claimed homosexuality rather than celibacy among the clergy, was at fault for the Church's child sex abuse scandal.

Cardinal Tarcisio Bertone denied celibacy was to blame for the sex scandals that have engulfed the Catholic Church, instead declaring that homosexuality and paedophilia were linked.

"Many psychologists, many psychiatrists have demonstrated there exists no relationship between celibacy and paedophilia," Bertone told a Santiago news conference during a visit to Chile.

"But many others have demonstrated, and have told me recently, that there is a link between homosexuality and paedophilia. This is true, this is the problem," he said.

The comments immediately threw fuel on the scandal that is threatening to engulf Pope Benedict XVI, by prompting outrage Tuesday in Chile and in Italy.

"I would like to see the scientific studies he said he has, because I don't share this evaluation... I have the impression that he is wrong on this point," said Patricio Walker, a Chilean senator who helped draft anti-paedophile laws.

Rolando Jimenez, head of Chile's Movement for Homosexual Integration and Liberation, called on Bertone "to show us any scientific, rigorous, serious and religiously independent study that supports this allegation."

In Rome, the head of Italian gay rights group Gaylib, Enrico Oliari, called it "worrying that the foreign minister of a state that occupies the heart of the Italian capital would use arguments that are considered passe even in the Third World."

The controversial statement came as the Vatican tried to step up its damage control on the scandal.

The leadership of the Catholic Church has repeatedly tried to dismiss as media exaggerations the tide of recent claims in Austria, Germany, Ireland and the United States that predator priests were given protection from prosecution by their hierarchy.

Pope Benedict himself has faced allegations that he failed to take action against paedophile priests, both as head of the Vatican's top doctrinal and morals enforcer and earlier as the Munich archbishop.